scholarly journals Mesoscopic metastable liquid in congruent vapor-liquid diagram of argon from about zero up to boyle`s temperature (review of FT-model)

Author(s):  
V.B. Rogankov ◽  
M.V. Shvets ◽  
O,V, Rogankov

Such paradigms of the coupled classical metastability and nonclassical criticality as the existence of a unified EOS (common for both gas and liquid phases) with its mean-field (mf), so-called Andrews-van der Waals’ critical point (CP) should be questioned to recognize the realistic stratified structure of a mesoscopic liquid phase. It exists supposedly in the wide range of temperatures located between about zero , K and up to the singular first Boyle’s point . Its opposite, also singular second Boyle’s point  corresponds to the alternative origin for the crossover continuous bounds separating the specific structural strata of a mesoscopic liquid. The region of a heterogeneous l-phase spanning the whole temperature range can be termed the non-Gibbsian phase (due to its discrete cluster-like structure) without any appeals to the concept of a spinodal decomposition. The respective metastable liquid stratum is formed by three segments of supercritical , subcritical  and sublimation  metastable states of a formally incompressible liquid constrained by the pair of fixed extensive parameters (N,V). Its location on the CVL-diagram is restricted by the new introduced here ml-bound and by the known Zeno-line (ZL) bound. Thus, all above-mentioned strata belong to the region of soft fluid with the dominance of interparticle attraction. The remaining parts of CVL-diagram are spanned either by the real gas state-points and solid state-points (crystalline and/or amorphous) or by the region of hard fluid in the classification proposed by Ben-Amotz and Herschbach.

Geophysics ◽  
2010 ◽  
Vol 75 (3) ◽  
pp. E123-E129 ◽  
Author(s):  
De-Hua Han ◽  
Min Sun ◽  
Micheal Batzle

Studies on how the velocity of [Formula: see text] is affected by temperature and pressure are important for understanding seismic properties of fluid and rock systems with a [Formula: see text] component. We carried out laboratory experiments to investigate velocity of [Formula: see text] in temperatures ranging from [Formula: see text] and pressures ranging from [Formula: see text], in which [Formula: see text] is in a liquid phase. The results show that under the above conditions, in general, the velocity of [Formula: see text] increases as pressure increases and temperature decreases. Near the critical point ([Formula: see text] and [Formula: see text]), the velocity of [Formula: see text] reaches a minimum and has a complicated behavior with temperature and pressure conditions due to the [Formula: see text] transition between gas and liquid phases. We also developed preliminary empirical models to calculate the velocity of [Formula: see text] based on newly measured data.


2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
R. M. Hughes ◽  
P. Mutzenhardt ◽  
A. A. Rodriguez

A previous study of C70 in deuterated benzenes generated evidence suggesting C70 exhibited unique reorientational behavior depending on its environment. We present a comparison of the dynamic behavior of this fullerene, in the solid and solution phases, to explore any unique features between these two phases. The effective correlation times, τCeff, of C70 in the solid state are 2 to 3 times longer than in solution. In the solid state, a noticeable decrease in all the carbons' correlation times is seen between 293 K to 303 K; suggesting a transition from isotropic to anisotropic reorientational behavior at this temperature change. Although C70 in solution experiences van der Waals type interactions, these interactions are not strong enough to slow the solution-state motion below what is observed in the solid state. All observed differences in the diffusion constants, DX and DZ, in solution are smaller than in the solid state suggesting a lower energy of activation between these two modes of reorientation in the liquid phase. A small-step diffusion “like” condition appears to be thermally generated in the solid phase at 323 K.


Nanophotonics ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 683-692 ◽  
Author(s):  
Entesar Al-Hetlani ◽  
Mohamed O. Amin ◽  
Metwally Madkour

AbstractThis work describes a novel and versatile solid-state chemiluminescence sensor for analyte detection using TiO2-Ru(bpy)32+-Ce(IV). Herein, we report the synthesis, characterization, optimization and application of a new type of hybrid nanoparticles (NPs). Mesoporous TiO2-Ru(bpy)32+ NPs were prepared using a modified sol-gel method by incorporating Ru(bpy)32+ into the initial reaction mixture at various concentrations. The resultant bright orange precipitate was characterized via transmission electron microscopy, N2 sorpometry, inductively coupled plasma-optical emission spectrometer (ICP-OES), Raman and UV-Vis spectroscopy techniques. The concentration of Ru(bpy)32+ complex in the NPs was quantified using ICP-OES, and its chemiluminescence (CL) response was measured and compared with the same concentration in the liquid phase using oxalate as model analyte. The results showed that this type of hybrid material exhibited a higher CL signal compared with the liquid phase due to the enlarged surface area of the hybrid NPs (~149.6 m2/g). The amount of TiO2-Ru(bpy)32+ NPs and the effect of the analyte flow rate were also investigated to optimize the CL signal. The optimized system was further used to detect oxalate and two pharmaceutical drugs, namely, imipramine and promazine. The linear range for both drugs was 1–100 pm with limits of detection (LOD) of 0.1 and 0.5 pm, respectively. This approach is considered to be simple, low cost and facile and can be applied to a wide range of analytes.


2007 ◽  
Vol 5 ◽  
pp. 113-120 ◽  
Author(s):  
R.Kh. Bolotnova

The method of construction the wide-range equations of state for organic liquids, describing the gas and liquid phases including dissociation and ionization which occurs during an intense collapse of steam bubbles and accompanied by ultra-high pressures and temperatures, is proposed.


2020 ◽  
Vol 21 (3) ◽  
pp. 211-220 ◽  
Author(s):  
Chandrasai Potla Durthi ◽  
Madhuri Pola ◽  
Satish Babu Rajulapati ◽  
Anand Kishore Kola

Aim & objective: To review the applications and production studies of reported antileukemic drug L-glutaminase under Solid-state Fermentation (SSF). Overview: An amidohydrolase that gained economic importance because of its wide range of applications in the pharmaceutical industry, as well as the food industry, is L-glutaminase. The medical applications utilized it as an anti-tumor agent as well as an antiretroviral agent. L-glutaminase is employed in the food industry as an acrylamide degradation agent, as a flavor enhancer and for the synthesis of theanine. Another application includes its use in hybridoma technology as a biosensing agent. Because of its diverse applications, scientists are now focusing on enhancing the production and optimization of L-glutaminase from various sources by both Solid-state Fermentation (SSF) and submerged fermentation studies. Of both types of fermentation processes, SSF has gained importance because of its minimal cost and energy requirement. L-glutaminase can be produced by SSF from both bacteria and fungi. Single-factor studies, as well as multi-level optimization studies, were employed to enhance L-glutaminase production. It was concluded that L-glutaminase activity achieved by SSF was 1690 U/g using wheat bran and Bengal gram husk by applying feed-forward artificial neural network and genetic algorithm. The highest L-glutaminase activity achieved under SSF was 3300 U/gds from Bacillus sp., by mixture design. Purification and kinetics studies were also reported to find the molecular weight as well as the stability of L-glutaminase. Conclusion: The current review is focused on the production of L-glutaminase by SSF from both bacteria and fungi. It was concluded from reported literature that optimization studies enhanced L-glutaminase production. Researchers have also confirmed antileukemic and anti-tumor properties of the purified L-glutaminase on various cell lines.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3790
Author(s):  
Yongzheng Ji ◽  
Tsuyoshi Honma ◽  
Takayuki Komatsu

Sodium super ionic conductor (NASICON)-type Na3Zr2Si2PO12 (NZSP) with the advantages of the high ionic conductivity, stability and safety is one of the most famous solid-state electrolytes. NZSP, however, requires the high sintering temperature about 1200 °C and long sintering time in the conventional solid-state reaction (SSR) method. In this study, the liquid-phase sintering (LPS) method was applied to synthesize NZSP with the use of NaPO3 glass with a low glass transition temperature of 292 °C. The formation of NZSP was confirmed by X-ray diffraction analyses in the samples obtained by the LPS method for the mixture of Na2ZrSi2O7, ZrO2, and NaPO3 glass. The sample sintered at 1000 °C for 10 h exhibited a higher Na+ ion conductivity of 1.81 mS/cm at 100 °C and a lower activation energy of 0.18 eV compared with the samples prepared by the SSR method. It is proposed that a new LPE method is effective for the synthesis of NZSP and the NaPO3 glass has a great contribution to the Na+ diffusion at the grain boundaries.


2021 ◽  
Vol 2 (1) ◽  
pp. 39-48
Author(s):  
Nguyen H. H. Phuc ◽  
Takaki Maeda ◽  
Tokoharu Yamamoto ◽  
Hiroyuki Muto ◽  
Atsunori Matsuda

A solid solution of a 100Li3PS4·xLi3PO4 solid electrolyte was easily prepared by liquid-phase synthesis. Instead of the conventional solid-state synthesis methods, ethyl propionate was used as the reaction medium. The initial stage of the reaction among Li2S, P2S5 and Li3PO4 was proved by ultraviolet-visible spectroscopy. The powder X-ray diffraction (XRD) results showed that the solid solution was formed up to x = 6. At x = 20, XRD peaks of Li3PO4 were detected in the prepared sample after heat treatment at 170 °C. However, the samples obtained at room temperature showed no evidence of Li3PO4 remaining for x = 20. Solid phosphorus-31 magic angle spinning nuclear magnetic resonance spectroscopy results proved the formation of a POS33− unit in the sample with x = 6. Improvements of ionic conductivity at room temperature and activation energy were obtained with the formation of the solid solution. The sample with x = 6 exhibited a better stability against Li metal than that with x = 0. The all-solid-state half-cell employing the sample with x = 6 at the positive electrode exhibited a better charge–discharge capacity than that employing the sample with x = 0.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1891
Author(s):  
Antonio Reina ◽  
Trung Dang-Bao ◽  
Itzel Guerrero-Ríos ◽  
Montserrat Gómez

Metal nanoparticles have been deeply studied in the last few decades due to their attractive physical and chemical properties, finding a wide range of applications in several fields. Among them, well-defined nano-structures can combine the main advantages of heterogeneous and homogenous catalysts. Especially, catalyzed multi-step processes for the production of added-value chemicals represent straightforward synthetic methodologies, including tandem and sequential reactions that avoid the purification of intermediate compounds. In particular, palladium- and copper-based nanocatalysts are often applied, becoming a current strategy in the sustainable synthesis of fine chemicals. The rational tailoring of nanosized materials involving both those immobilized on solid supports and liquid phases and their applications in organic synthesis are herein reviewed.


2016 ◽  
Vol 4 (16) ◽  
pp. 3599-3606 ◽  
Author(s):  
Toshiki Mutai ◽  
Tatsuya Ohkawa ◽  
Hideaki Shono ◽  
Koji Araki

The color of ESIPT luminescence of HPIP is tuned in a wide range by the introduction of aryl group(s), and thus a series of PIPs showing blue to red emission is realized.


Sign in / Sign up

Export Citation Format

Share Document